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added PAGE_DIR_SELF_REF2 to fix bug in page directory self-referencing

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git-svn-id: svn://anubis/hos/trunk@100 5b3e749e-e535-0410-8002-a9bb6afbdfca
This commit is contained in:
josh 2010-02-01 04:21:29 +00:00
parent ae5dc7df6f
commit 563758b1bd
3 changed files with 7 additions and 6 deletions
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2
kernel/include/hos_defines.h
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@ -6,7 +6,7 @@
#define KERNEL_OFFSET 0x00000000
#define PAGE_LOG_SIZE 12
#define PAGE_LOG_SIZE 12u
#define PAGE_SIZE (1 << PAGE_LOG_SIZE)
#define PAGE_HIGH_MASK (0xFFFFFFFFu << PAGE_LOG_SIZE)
#define PAGE_LOW_MASK (0xFFFFFFFFu >> (32 - PAGE_LOG_SIZE))

8
kernel/mm/mm.cc
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@ -147,7 +147,7 @@ void mm_bootstrap()
/* ok, now mm_early_map() should be functional */
/* map in the page directory itself so we can modify it once paging is on */
mm_early_map(PAGE_DIR_SELF_REF, page_directory_phys, 0, 1);
mm_early_map(PAGE_DIR_SELF_REF2, page_directory_phys, 0, 1);
/* map in the physical page allocator pages */
for (int i = 0; i <= last_page_alloc_page; i++)
@ -262,7 +262,8 @@ int mm_early_map(u32_t virtual_address, u32_t physical_address,
u32_t page_table_phys =
(*early_page_directory_ptr)[directory_index] & PAGE_HIGH_MASK;
u32_t * page_table = (u32_t *) (page_table_phys + KERNEL_OFFSET);
pagedirectory_entry_t * page_table =
(pagedirectory_entry_t *) (page_table_phys + KERNEL_OFFSET);
page_table[table_index] = (physical_address & PAGE_HIGH_MASK)
| (user_mode & 0x1) << 2
@ -282,8 +283,7 @@ int mm_map(u32_t virtual_address, u32_t physical_address,
u32_t directory_index = (virtual_address >> 22) & 0x3FF;
u32_t table_index = (virtual_address >> 12) & 0x3FF;
pagedirectory_entry_t * page_dir_entry = (pagedirectory_entry_t *)
(PAGE_DIR_SELF_REF | (PAGE_DIR_SELF_REF_INDEX << 12)
| (directory_index << 2));
(PAGE_DIR_SELF_REF2 | (directory_index << 2));
if (*page_dir_entry == 0)
{

3
kernel/mm/mm.h
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@ -13,8 +13,9 @@ typedef u32_t pagedirectory_entry_t;
#define NUM_PAGETABLE_ENTRIES (PAGE_SIZE / sizeof(pagedirectory_entry_t))
#define PAGE_DIR_SELF_REF (0x20000000 - (PAGE_SIZE * NUM_PAGETABLE_ENTRIES))
#define PAGE_DIR_SELF_REF (0x20000000u - (PAGE_SIZE * NUM_PAGETABLE_ENTRIES))
#define PAGE_DIR_SELF_REF_INDEX ((PAGE_DIR_SELF_REF >> 22) & 0x3FF)
#define PAGE_DIR_SELF_REF2 (PAGE_DIR_SELF_REF | (PAGE_DIR_SELF_REF_INDEX << 12))
typedef pagedirectory_entry_t pagedirectory_t[NUM_PAGETABLE_ENTRIES];